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Feng-Yee Chang

Publications and source records attributed to Feng-Yee Chang.

At least 19 recordsLinked to original sources
PubMed2006

Capsular serotype K1 or K2, rather than magA and rmpA, is a major virulence determinant for Klebsiella pneumoniae liver abscess in Singapore and Taiwan.

Capsular serotypes, magA, and rmpA have been documented in high prevalence for Klebsiella pneumoniae liver abscess. To investigate the regional difference and the correlation of capsular serotype, magA, and rmpA with virulence, 73 isolates were collected in Singapore and Taiwan. Capsular serotypes were determined by countercurrent immunoelectrophoresis, the presence of magA and rmpA was determined by PCR, and virulence was determined by phagocytosis and mouse inoculation. Isolates from Singapore were similar to those from Taiwan in genomic heterogeneity, prevalence of serotype, and the presence of magA and rmpA. The most common serotype was K1 (34/73; 46.6%), followed by K2 (15/73; 20.5%). magA was restricted to serotype K1. All K1 or K2 isolates and 66.7% (16/24) of isolates that were neither serotype K1 nor serotype K2 (non-K1/K2) carried rmpA. Serotype K1 or K2 isolates demonstrated significantly more phagocytic resistance and virulence than did rmpA-positive and -negative groups of non-K1/K2 isolates. In the non-K1/K2 group, the virulence profiles of rmpA-positive strains from Taiwan and Singapore were different by phagocytosis assay and in the mouse model, indicating that factors other than rmpA contributed to virulence. The characteristics of K. pneumoniae liver abscess in Singapore and Taiwan are similar. Capsular serotype K1 or K2 plays a more important role than magA and rmpA in determining virulence in K. pneumoniae liver abscess.

Animals↗
PubMed2006

Nosocomial liver abscess caused by extended-spectrum beta-lactamase-producing Klebsiella pneumoniae.

A nosocomial pyogenic liver abscess caused by an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae isolate presented in a man with adenocarcinoma of the stomach. The K. pneumoniae strain isolated from blood and liver aspirate cultures after antibiotic therapy for recurrent bacteremia was resistant to all extended-spectrum beta-lactams except imipenem and differed from K. pneumoniae strains causing community-acquired liver abscesses.

Adenocarcinoma↗
PubMed2006

Characterization of acquired beta-lactamases and their genetic support in multidrug-resistant Pseudomonas aeruginosa isolates in Taiwan: the prevalence of unusual integrons.

OBJECTIVES: The present study was conducted to investigate acquired beta-lactamases and their genetic support in 26 Pseudomonas aeruginosa isolates that were resistant to nearly all antipseudomonal drugs from six medical centres in Taiwan. METHODS: Acquired beta-lactamases and their genetic support were determined by PCR-based strategies. RESULTS: Four and 16 of the 26 isolates were found to produce VIM-2 and VIM-3 metallo-beta-lactamases (MBLs), respectively, and 1, 1 and 2 isolates produced OXA-17, OXA-10 and PSE-1, respectively. These bla genes are all in class 1 integrons that are probably chromosomally located. The bla(VIM-3)-containing integron, with a deletion between int1 and the bla(VIM-3) structural gene, has six gene cassettes, bla(VIM-3), a probable fosfomycin resistance determinant, aacA4, aacA4, aadB and aacA4. The bla(VIM-2)-containing integron, without detectable 5'-conserved segment, contains four genes cassettes (aacA7-bla(VIM-2)-dhfr-aacA5) and is ended by tniC. The bla(OXA-10)-containing integron includes a catB3 cassette and a fused gene cassette, which is made up of bla(OXA-17) and a novel streptomycin-spectinomycin gene, designated aadA15. The bla(OXA-17)-containing integron has three gene cassettes (aacA4-catB2-bla(OXA-17)) but the 59-base element of the bla(OXA-17) cassette is interrupted by a putative transposase gene. The bla(PSE-1)-containing integron has three gene cassettes, aacA4, an aadA3-related gene designated aadA3b and bla(PSE-1). PFGE revealed genetic diversity among the multidrug-resistant isolates from different hospitals. CONCLUSIONS: This study demonstrated the high prevalence of VIM-type MBLs and the presence of unusual bla-encoding integrons in multidrug-resistant P. aeruginosa isolates in Taiwan. The spread of bla(VIM-2)-related genes by horizontal transfer might have occurred.

Anti-Bacterial Agents↗
PubMed2006

Impaired phagocytosis of capsular serotypes K1 or K2 Klebsiella pneumoniae in type 2 diabetes mellitus patients with poor glycemic control.

CONTEXT: Diabetes mellitus (DM) and capsular serotypes K1 and K2 Klebsiella pneumoniae have been identified as risk factors for liver abscess and complicated endophthalmitis. OBJECTIVE: The objective of this study was to determine whether poor glycemic control contributes to the development of capsular serotype K1 or K2 K. pneumoniae liver abscess. DESIGN AND SETTING: Neutrophil phagocytosis in patients with type 2 DM and nondiabetic controls was compared with isolates from liver abscess. Phagocytic rates of 18 K1/K2 and nine non-K1/K2 K. pneumoniae strains were evaluated by flow cytometry and electron microscopy. PATIENTS OR STUDY PARTICIPANTS: Forty patients with type 2 diabetes, 14 with good glycemic control, 26 with poor glycemic control, and 13 age-matched healthy normal subjects, were studied. MAIN OUTCOME MEASURES: Phagocytic rate of K. pneumoniae was measured. RESULTS: Phagocytosis of serotype K1/K2 isolates by neutrophils from diabetics was significantly less than normal controls (P < 0.01). Further analysis revealed that, in type 2 DM patients with poor glycemic control, phagocytosis of K1/K2 was remarkably impaired at 10 min (25.2 +/- 1.7 vs. 42.4 +/- 1.8%) and persisted until 60 min (51 +/- 1.2 vs. 59.4 +/- 1.4%; P < 0.01), but in type 2 DM patients with good glycemic control were similar at 10 min (38.2 +/- 1.7% vs. 42.4 +/- 1.8%) and at 60 min (57 +/- 0.3% vs. 59.4 +/- 1.4%; P = 0.2). No significant difference in the phagocytosis of non-K1/K2 K. pneumoniae among all subjects was observed. CONCLUSIONS: Poor glycemic control plays a role in impairing neutrophil phagocytosis of K1/K2 K. pneumoniae, but does not significantly affect the phagocytosis of non-K1/K2 K. pneumoniae. This study identifies poor glycemic control as a risk factor for susceptibility to serotype K1/K2 K. pneumoniae liver abscess and complicated endophthalmitis.

Adult↗
PubMed2006

Pylephlebitis associated with acute infected choledocholithiasis.

Pylephlebitis, also called septic thrombophlebitis of the portal vein, is a life-threatening complication of intra-abdominal infection. Although rare, it remains a less recognized entity with a high rate of mortality. We present a 66-year-old man with acute infected choledocholithiasis complicated with Bacteroides fragilis bacteremia. The contrast-enhanced computed tomography scan of the abdomen showed nearly total thrombotic occlusion of the left portal vein. The comprehensive studies for hypercoagulation disorders all yielded negative results. After endoscopic extraction of bile duct stones and broad-spectrum antibiotic therapy, the patient recuperated with complete recanalization of the occluded portal vein. To our knowledge, pylephlebitis associated with acute infected choledocholithiasis has never been reported. This report details the clinical features, radiographic findings, pathogenesis, and treatment of this distinctly unusual manifestation. Early identification of pylephlebitis and underlying intra-abdominal infection can be achieved by exquisite imaging studies with raised awareness in the clinical setting. Eradication of infectious foci and judicious administration of antimicrobials are essential to reduce the catastrophic morbidity and mortality of pylephlebitis.

Abdominal Cavity↗
PubMed2006

Extended-spectrum beta-lactamases and plasmid-mediated AmpC enzymes among clinical isolates of Escherichia coli and Klebsiella pneumoniae from seven medical centers in Taiwan.

Production of extended-spectrum beta-lactamases and plasmid-mediated AmpC enzymes was investigated among 291 Escherichia coli and 282 Klebsiella pneumoniae isolates that showed decreased susceptibilities to extended-spectrum cephalosporins from seven Taiwanese medical centers. CTX-M-type and SHV-type enzymes were the most prevalent extended-spectrum beta-lactamases. CMY-2-like and DHA-1-like beta-lactamases were the most prevalent AmpC-type enzymes.

Anti-Bacterial Agents↗
PubMed2005

Experience of using convalescent plasma for severe acute respiratory syndrome among healthcare workers in a Taiwan hospital.

OBJECTIVES: To describe the immunological responses and clinical outcome of coronavirus (SARS) infected healthcare workers (HCW) who had been administered with convalescent plasma as a treatment. METHODS: Convalescent plasma (500 mL) was obtained from each of three SARS patients and transfused into the three infected HCW. Donors were blood type O and seronegative for hepatitis B and C, HIV, syphilis and human T-cell lymphotropic virus types I and II (HTLV-I and -II). Serum antibody (IgG) titre was >640. Apharesis was performed with a CS 3000 plus cell separator followed by the forming of the convalescent phase plasma. As part of the routine check with donated plasma, the convalescent plasma was confirmed free of residual SARS-CoV by RT-PCR. Serial serum samples obtained from the recipients of the convalescent plasma were collected to undertake real-time quantitative RT-PCR for SARS-CoV for direct measurement of viral concentration. Specific immunoglobulin IgM and IgG concentrations were titrated using an antigen microarray developed in-house. RESULTS: Viral load dropped from 495 x 10(3), 76 x 10(3) or 650 x 10(3) copies/mL to zero or 1 copy/mL one day after transfusion. Anti-SARS-CoV IgM and IgG also increased in a time-dependent manner following transfusion. All three patients survived. One HCW became pregnant subsequently, delivering 13 months after discharge. Positive anti-SARS-CoV IgG was detected in the newborn. Passive transfer of anti-SARS-CoV antibody from the mother was considered as a possibility. CONCLUSIONS: All infected HCW whose condition had progressed severely and who had failed to respond to the available treatment, survived after transfusion with convalescent plasma.

Adult↗
PubMed2005

Etiology of community acquired pneumonia among adult patients requiring hospitalization in Taiwan.

BACKGROUND: There has not been a comprehensive multi-center study investigating the microbial profile of community acquired pneumonia (CAP) in Taiwan. METHODS: A prospective study of adult CAP patients requiring hospitalization between December 2001 and April 2002 was carried out in 13 hospitals in Taiwan. Etiology was determined based on laboratory data from blood and sputum cultures plus serology from paired serum and urine antigen detection tests. RESULTS: Etiology was assigned to 99 (58.9%) of the 168 patients having the most complete data for etiology determination, with mixed infection in 21 (12.5%) patients. More than half (51.8%) of the patients were>60 years and 63.7% of the patients were males. The most common etiologic agent was Streptococcus pneumoniae (40, 23.8%), the majority (60%, 24 cases) of which was detected by positive urine antigen test. Other common agents included Mycoplasma pneumoniae (24, 14.3%), Chlamydia pneumoniae (12, 7.1%), Influenza A virus (11, 6.5%), Klebsiella pneumoniae (8, 4.8%) and Haemophilus influenzae (8, 4.8%). The prevalence of S. pneumoniae and M. pneumoniae was highest in patients>60 years (25/87, 28.7%), and<44 years (12/59, 19%), respectively; while K. pneumoniae comprised a larger proportion (4/22, 18%) in the 45-59 years group. CONCLUSIONS: S. pneumoniae was the most common etiology agent in adult patients hospitalized due to CAP in Taiwan and the spectrum of other major pathogens was similar to studies conducted elsewhere in the world. Empiric treatment recommendations developed in other parts of the world may be appropriately adapted for local use after taking into account local resistance profiles. Our data also support the recommendation that urine antigen test be added as an adjunct to adult CAP etiology diagnosis protocol.

Adolescent↗
PubMed2005

Acute quadriplegia complicating critical illness polyneuropathy in a patient with infective endocarditis: a case report.

A 75-year-old woman with infective endocarditis developed critical illness polyneuropathy (CIP) with quadriplegia after cardiac surgery. The quadriplegia resolved gradually after aggressive treatment of the underlying infection and with rehabilitation. However, a MEDLINE search of the English-language literature failed to yield results matching quadriplegia and infective endocarditis. CIP is a complication of septic syndrome and sepsis. This complication has been largely unrecognized in intensive care units owing to difficulties in performing a clinical examination or electrophysiologic studies. Difficulty in weaning from the ventilator is an important early manifestation of CIP. Electroneuromyography (ENMG) should be routinely performed to establish the diagnosis. We suggest that any septic patients with unexplained muscle weakness, paralysis, or difficulty in weaning from the ventilator should be evaluated for CIP.

Acute Disease↗
PubMed2005

Variety of TEM-, SHV-, and CTX-M-type beta-lactamases present in recent clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae from Taiwan.

A total of 171 hospitals' isolates of E. coli, K. pneumoniae, and E. cloacae with a minimum inhibitory concentration (MIC) of > or =2 microg/ml for ceftazidime or cefotaxime were evaluated for the production of beta-lactamases. PCR amplification with specific primers for the bla (SHV), bla (TEM), and bla (CTX) genes revealed that a total of 53, 81, and 43 of these genes were amplified, respectively. Sequencing results confirmed that TEM-1, CTX-M-3 and -14, SHV-1, -5, -11, -12, and -33, OXY-1a, and LEN-1 were presented among these isolates. No specific large cluster of isolates carried the same beta-lactamases, indicating the wide diversity of the collected strains. Plasmid spread between E. coli and K. pneumoniae was identified in few isolates. Combinations of TEM, SHV, and CTX beta-lactamase genes, including extended-spectrum beta-lactamase genes, were observed in all three species.

Enterobacteriaceae↗
PubMed2005

Prospective randomized comparison of single-dose versus 1-day cefazolin for prophylaxis in gynecologic surgery.

BACKGROUND: The purpose of this prospective, randomized study was to compare the efficacy of single-dose versus 1-day cefazolin prophylaxis for the prevention of postoperative gynecologic infections. METHODS: From June 2001 to January 2003, 548 patients were randomized to receive either single-dose (1 g of cefazolin intravenously before surgery, 273 patients) or 1-day cefazolin (1 g intravenously before surgery and three more doses every 6 hr after surgery, 275 patients) prophylaxis. RESULTS: A total of 531 (267 patients in the single-dose group and 264 in the 1-day group) completed the study. Only one of 267 (0.37%) patients in the single-dose group developed a trocar wound infection and one of 264 (0.37%) patients in the 1-day group developed a vaginal cuff infection. Had a single dose of prophylactic antibiotics been administered to all patients, the antibiotic cost would have been reduced by 75-80%. CONCLUSIONS: The use of single-dose preoperative cefazolin prophylaxis was as effective as four doses of cefazolin for preventing serious infectious morbidity among our patients. Shortening the duration of antibiotics prophylaxis also reduced medical costs and microorganism resistance.

Adult↗
PubMed2005

Novel SHV-derived extended-spectrum beta-lactamase, SHV-57, that confers resistance to ceftazidime but not cefazolin.

A new SHV-derived extended-spectrum beta-lactamase, SHV-57, that confers high-level resistance to ceftazidime but not cefotaxime or cefazolin was identified from a national surveillance study conducted in Taiwan in 1998. An Escherichia coli isolate resistant to ampicillin, cephalothin, and ceftazidime but sensitive to cefoxitin, ceftriaxone, cefotaxime, imipenem, and a narrow-spectrum cephem (cefazolin) was isolated from the urine of a patient treated with beta-lactam antibiotics. Resistance to beta-lactams was conjugatively transferred with a plasmid of about 50 kbp. The pI of this enzyme was 8.3. The sequence of the gene was determined, and the open reading frame of the gene was found to consist of 861 bases (GenBank accession number AY223863). Kinetic parameters showed that SHV-57 had a poor affinity to cefazolin. The K(m) value toward cefazolin (5.57 x 10(3) muM) was extremely high in comparison to those toward ceftazidime (30.9 muM) and penicillin G (67 muM), indicating its low affinity to cefazolin. Although the K(m) value of the beta-lactamase inhibitor was too high for the study of catalytic activity (k(cat)), indicating the low k(cat) of SHV-57, the SHV-57 carrier was highly susceptible to a beta-lactam-beta-lactamase inhibitor combination. Comparison of the three-dimensional molecular model of SHV-57 with that of the SHV-1 beta-lactamase suggests that the substitution of arginine for leucine-169 in the Omega loop is important for the substrate specificity.

Cefazolin↗
PubMed2005

Rapidly progressive necrotizing fasciitis caused by Staphylococcus aureus.

Necrotizing fasciitis (NF) is a rapidly progressive life-threatening infection located in the deep fascia, with secondary necrosis of the subcutaneous tissues. Staphylococcus aureus as a single etiologic agent is rare. The pathogenicity of S. aureus infections is related to various bacterial surface components and extracellular proteins. A 56-year-old man developed fever, hypotension, impaired renal and hepatic functions, disseminated intravascular coagulation, and rapidly progressive NF affecting the 4 extremities due to methicillin-susceptible S. aureus (MSSA). The initial presenting symptoms were general weakness and muscular pain over bilateral thighs and left shoulder, and gradual onset of weakness of the limbs. On the third hospital day, multiple red-purplish discoloration spread across the right lower leg and left forearm. Fasciotomy and debridement was performed on the fifth hospital day, and the diagnosis of NF was confirmed. MSSA was the only pathogen isolated from 4 sets of blood cultures taken on admission and cultures of tissues collected during surgical debridement. The disease progressed rapidly over the 4 extremities despite appropriate antibiotic treatment. He recovered after multiple extensive surgical interventions and 8 weeks of intensive medical care. Early diagnosis, intensive surgical intervention, antibiotic treatment and intensive medical care are crucial for a successful outcome in patients with septic shock and extensive NF caused by S. aureus.

Anti-Bacterial Agents↗
PubMed2005

Lemierre's syndrome.

Lemierre's syndrome is a rare, potentially severe disease consisting of septic emboli from an internal jugular vein thrombus after oropharyngeal infection. We report a 20-year-old man who had a tonsillitis with fever for 3 days. After a 2-day defervescence, fever relapsed as well as painful swelling over the left side of the neck. Computed tomography scan and sonography of the neck revealed thrombosis of left internal jugular vein and swelling of surrounding soft tissue. Chest radiograph demonstrated cavitary infiltrates over the left upper lobe. Septic thrombophlebitis of the internal jugular vein and metastatic pulmonary emboli was highly suspected. Intravenous ceftriaxone and metronidazole were given empirically. Fusobacterium necrophorum was isolated from the blood culture with susceptibility to metronidazole. Complete defervescence and resolution of the neck swelling and pulmonary infiltrates occurred after antibiotic administration for 21 days. Lemierre's syndrome should be considered when encountering a febrile patient with painful neck swelling.

Adult↗
PubMed2004

Plasma proteome of severe acute respiratory syndrome analyzed by two-dimensional gel electrophoresis and mass spectrometry.

We have investigated the plasma proteome by using 2D gel electrophoresis and MS from patients with severe acute respiratory syndrome (SARS). A complete proteomic analysis was performed on four patients with SARS in different time courses, and a total of 38 differential spots were selected for protein identification. Most of the proteins identified are acute phase proteins, and their presence represents the consequence of serial cascades initiated by SARS-coronavirus infection. There are several proteins that have never been identified in plasma before using 2D gel electrophoresis, among which peroxiredoxin II was chosen for further study by analyzing additional 20 plasma samples from patients with probable and suspected SARS and patients with fever, respectively. The results showed that the level of plasma peroxiredoxin II in patients with SARS is significantly high and could be secreted by T cells. Taken together, our findings indicate that active innate immune responses, along with the oxidation-associated injuries, may play a major role in the pathogenesis of SARS.

Acute-Phase Proteins↗